source/glsl/finalize.cpp

   1 #include <msp/core/algorithm.h>
   2 #include <msp/core/raii.h>
   3 #include <msp/strings/lexicalcast.h>
   4 #include "finalize.h"
   5 #include "glsl_error.h"
   6
   7 using namespace std;
   8
   9 namespace Msp {
  10 namespace GL {
  11 namespace SL {
  12
  13 PrecisionConverter::PrecisionConverter():
  14         stage(0)
  15 { }
  16
  17 void PrecisionConverter::apply(Stage &s)
  18 {
  19         stage = &s;
  20         s.content.visit(*this);
  21         NodeRemover().apply(s, nodes_to_remove);
  22 }
  23
  24 void PrecisionConverter::visit(Block &block)
  25 {
  26         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
  27         {
  28                 if(&block==&stage->content)
  29                         insert_point = i;
  30                 (*i)->visit(*this);
  31         }
  32 }
  33
  34 void PrecisionConverter::visit(Precision &prec)
  35 {
  36         if(stage->required_features.gl_api==OPENGL_ES2)
  37                 have_default.insert(prec.type);
  38         else
  39                 nodes_to_remove.insert(&prec);
  40 }
  41
  42 void PrecisionConverter::visit(VariableDeclaration &var)
  43 {
  44         if(stage->required_features.gl_api!=OPENGL_ES2)
  45         {
  46                 var.precision.clear();
  47                 return;
  48         }
  49
  50         const char *default_prec = (stage->type==Stage::FRAGMENT ? "mediump" : "highp");
  51         const TypeDeclaration *type = var.type_declaration;
  52         while(type)
  53         {
  54                 if(dynamic_cast<const ImageTypeDeclaration *>(type))
  55                 {
  56                         default_prec = "lowp";
  57                         break;
  58                 }
  59                 else if(const BasicTypeDeclaration *basic = dynamic_cast<const BasicTypeDeclaration *>(type))
  60                 {
  61                         if(basic->kind==BasicTypeDeclaration::INT || basic->kind==BasicTypeDeclaration::FLOAT)
  62                                 break;
  63                         type = basic->base_type;
  64                 }
  65                 else
  66                         return;
  67         }
  68         if(!type)
  69                 return;
  70
  71         if(!have_default.count(type->name))
  72         {
  73                 Precision *prec = new Precision;
  74                 prec->precision = default_prec;
  75                 prec->type = type->name;
  76                 stage->content.body.insert(insert_point, prec);
  77
  78                 have_default.insert(type->name);
  79         }
  80 }
  81
  82
  83 LegacyConverter::LegacyConverter():
  84         frag_out(0)
  85 { }
  86
  87 void LegacyConverter::apply(Stage &s, const Features &feat)
  88 {
  89         stage = &s;
  90         features = feat;
  91         if(supports_stage(s.type))
  92         {
  93                 s.content.visit(*this);
  94                 NodeRemover().apply(s, nodes_to_remove);
  95
  96                 if(!stage->required_features.glsl_version)
  97                         stage->required_features.glsl_version = Version(1, (stage->required_features.gl_api==OPENGL_ES2 ? 0 : 10));
  98         }
  99         else
 100                 unsupported(format("Stage %s is not supported", Stage::get_stage_name(s.type)));
 101 }
 102
 103 void LegacyConverter::unsupported(const string &reason)
 104 {
 105         Diagnostic diagnostic;
 106         diagnostic.severity = Diagnostic::ERR;
 107         diagnostic.source = GENERATED_SOURCE;
 108         diagnostic.line = 0;
 109         diagnostic.message = reason;
 110         stage->diagnostics.push_back(diagnostic);
 111 }
 112
 113 void LegacyConverter::visit(Block &block)
 114 {
 115         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
 116         {
 117                 if(&block==&stage->content)
 118                         uniform_insert_point = i;
 119                 (*i)->visit(*this);
 120         }
 121 }
 122
 123 bool LegacyConverter::check_version(const Version &feature_version) const
 124 {
 125         if(features.glsl_version<feature_version)
 126                 return false;
 127         else if(stage->required_features.glsl_version<feature_version)
 128                 stage->required_features.glsl_version = feature_version;
 129
 130         return true;
 131 }
 132
 133 bool LegacyConverter::check_extension(bool Features::*extension) const
 134 {
 135         if(!(features.*extension))
 136                 return false;
 137
 138         stage->required_features.*extension = true;
 139
 140         return true;
 141 }
 142
 143 bool LegacyConverter::supports_stage(Stage::Type st) const
 144 {
 145         if(st==Stage::GEOMETRY)
 146         {
 147                 if(features.gl_api==OPENGL_ES2)
 148                         return check_version(Version(3, 20));
 149                 else
 150                         return check_version(Version(1, 50));
 151         }
 152         else
 153                 return true;
 154 }
 155
 156 bool LegacyConverter::supports_unified_interface_syntax() const
 157 {
 158         if(features.gl_api==OPENGL_ES2)
 159                 return check_version(Version(3, 0));
 160         else
 161                 return check_version(Version(1, 30));
 162 }
 163
 164 void LegacyConverter::visit(VariableReference &var)
 165 {
 166         if(var.declaration==frag_out && !supports_unified_interface_syntax())
 167         {
 168                 var.name = "gl_FragColor";
 169                 var.declaration = 0;
 170         }
 171 }
 172
 173 void LegacyConverter::visit(Assignment &assign)
 174 {
 175         TraversingVisitor::visit(assign);
 176         if(assign.target.declaration==frag_out && !supports_unified_interface_syntax())
 177                 assign.target.declaration = 0;
 178 }
 179
 180 bool LegacyConverter::supports_unified_sampling_functions() const
 181 {
 182         if(features.gl_api==OPENGL_ES2)
 183                 return check_version(Version(3, 0));
 184         else
 185                 return check_version(Version(1, 30));
 186 }
 187
 188 void LegacyConverter::visit(FunctionCall &call)
 189 {
 190         if(call.declaration && call.declaration->source==BUILTIN_SOURCE)
 191         {
 192                 if(!call.name.compare(0, 7, "texture") && call.arguments.size()>=1)
 193                 {
 194                         const ImageTypeDeclaration *arg_image = dynamic_cast<const ImageTypeDeclaration *>(call.arguments.front()->type);
 195                         if(arg_image && !supports_unified_sampling_functions())
 196                         {
 197                                 string suffix = call.name.substr(7);
 198                                 call.name = (arg_image->shadow ? "shadow" : "texture");
 199
 200                                 switch(arg_image->dimensions)
 201                                 {
 202                                 case ImageTypeDeclaration::ONE: call.name += "1D"; break;
 203                                 case ImageTypeDeclaration::TWO: call.name += "2D"; break;
 204                                 case ImageTypeDeclaration::THREE: call.name += "3D"; break;
 205                                 case ImageTypeDeclaration::CUBE: call.name += "Cube"; break;
 206                                 }
 207
 208                                 if(arg_image->array)
 209                                 {
 210                                         /* Array textures and the unified sampling function name were
 211                                         both introduced in GLSL 1.30. */
 212                                         if(arg_image->dimensions==ImageTypeDeclaration::ONE || arg_image->dimensions==ImageTypeDeclaration::TWO)
 213                                                 check_extension(&Features::ext_texture_array);
 214                                         call.name += "Array";
 215                                 }
 216
 217                                 call.name += suffix;
 218                         }
 219                 }
 220         }
 221
 222         TraversingVisitor::visit(call);
 223 }
 224
 225 bool LegacyConverter::supports_interface_layouts() const
 226 {
 227         if(features.gl_api==OPENGL_ES2)
 228                 return check_version(Version(3, 0));
 229         else if(check_version(Version(3, 30)))
 230                 return true;
 231         else
 232                 return check_extension(&Features::arb_explicit_attrib_location);
 233 }
 234
 235 bool LegacyConverter::supports_centroid_sampling() const
 236 {
 237         if(features.gl_api==OPENGL_ES2)
 238                 return check_version(Version(3, 0));
 239         else if(check_version(Version(1, 20)))
 240                 return true;
 241         else
 242                 return check_extension(&Features::ext_gpu_shader4);
 243 }
 244
 245 bool LegacyConverter::supports_sample_sampling() const
 246 {
 247         if(features.gl_api==OPENGL_ES2)
 248                 return check_version(Version(3, 20));
 249         else if(check_version(Version(4, 0)))
 250                 return true;
 251         else
 252                 return check_extension(&Features::arb_gpu_shader5);
 253 }
 254
 255 void LegacyConverter::visit(VariableDeclaration &var)
 256 {
 257         if(var.layout)
 258         {
 259                 for(vector<Layout::Qualifier>::const_iterator i=var.layout->qualifiers.begin(); i!=var.layout->qualifiers.end(); )
 260                 {
 261                         if(i->name=="location" && !supports_interface_layouts())
 262                         {
 263                                 if(stage->type==Stage::VERTEX && var.interface=="in")
 264                                         stage->locations[var.name] = i->value;
 265                                 else if(stage->type==Stage::FRAGMENT && var.interface=="out")
 266                                 {
 267                                         if(check_extension(&Features::ext_gpu_shader4))
 268                                                 stage->locations[var.name] = i->value;
 269                                         else if(i->value!=0)
 270                                                 unsupported("EXT_gpu_shader4 required for multiple fragment shader outputs");
 271                                 }
 272
 273                                 i = var.layout->qualifiers.erase(i);
 274                         }
 275                         else
 276                                 ++i;
 277                 }
 278
 279                 if(var.layout->qualifiers.empty())
 280                         var.layout = 0;
 281         }
 282
 283         if(var.sampling=="centroid")
 284         {
 285                 if(!supports_centroid_sampling())
 286                         var.sampling = string();
 287         }
 288         else if(var.sampling=="sample")
 289         {
 290                 if(!supports_sample_sampling())
 291                         var.sampling = string();
 292         }
 293
 294         if((var.interface=="in" || var.interface=="out") && !supports_unified_interface_syntax())
 295         {
 296                 if(stage->type==Stage::FRAGMENT && var.interface=="out")
 297                 {
 298                         frag_out = &var;
 299                         nodes_to_remove.insert(&var);
 300                 }
 301         }
 302
 303         TraversingVisitor::visit(var);
 304 }
 305
 306 bool LegacyConverter::supports_interface_blocks(const string &iface) const
 307 {
 308         if(features.gl_api==OPENGL_ES2)
 309         {
 310                 if(iface=="uniform")
 311                         return check_version(Version(3, 0));
 312                 else
 313                         return check_version(Version(3, 20));
 314         }
 315         else if(check_version(Version(1, 50)))
 316                 return true;
 317         else if(iface=="uniform")
 318                 return check_extension(&Features::arb_uniform_buffer_object);
 319         else
 320                 return false;
 321 }
 322
 323 void LegacyConverter::visit(InterfaceBlock &iface)
 324 {
 325         if(!supports_interface_blocks(iface.interface) && iface.type_declaration)
 326         {
 327                 if(!iface.instance_name.empty())
 328                         unsupported("ARB_uniform_buffer_object required for interface block instances");
 329                 else if(iface.struct_declaration)
 330                 {
 331                         stage->content.body.splice(uniform_insert_point, iface.struct_declaration->members.body);
 332                         nodes_to_remove.insert(&iface);
 333                         nodes_to_remove.insert(iface.struct_declaration);
 334                 }
 335                 else
 336                         /* If the interface block is an array, it should have an instance
 337                         name too, so this should never be reached */
 338                         throw logic_error("Unexpected interface block configuration");
 339         }
 340 }
 341
 342 } // namespace SL
 343 } // namespace GL
 344 } // namespace Msp